α-olefin polymerization catalyst component

ABSTRACT

This invention relates to a catalytic component for the polymerization of α-olefins and provides a catalytic component of magnesium support type capable of exhibiting a high stereoregularity while maintaining an improved strength as well as a high catalytic activity. The features thereof consist in a catalyst component for the polymerization of α-olefins obtained by contacting (A) a solid component comprising, as essential components, magnesium, titanium, a halogen and an electron-donating compound with (D) an olefin in the presence of (B) a trialkylaluminum and (C) a dimethoxy group-containing compound represented by the general formula R 1  R 2  Si(OCH 3 ) 2  where R 1  and R 2  are, same or different, aliphatic hydrocarbon groups with 1 to 10 carbon atoms and having a volume, calculated by the quantum chemistry calculation, of 230 to 500 Å 3  and an electron density of oxygen atoms in the methoxy group, calculated similarly, ranging from 0.685 to 0.800 A. U. (atomic unit) and a catalyst component for the polymerization of α-olefins obtained by contacting (A) a solid component comprising, as essential components, a metal oxide, magnesium, titanium, a halogen and an electron-donating compound with (D) an olefin in the presence of (B) a trialkylaluminum and (C) a dimethoxy group-containing compound represented by the general formula R 1  R 2  Si(OCH 3 ) 2  where R 1  and R 2  are, same or different, aliphatic hydrocarbon groups with 1 to 10 carbon atoms and having a volume calculated by the quantum chemistry calculation, of 170 to 500 Å 3  and an electron density of oxygen atoms in the methoxy group, calculated similarly, ranging from 0.690 to 0.800 A. U. (atomic unit) or the volume in the range of 200 to 500 Å 3  and the electron density in the range of 0.685 to 0.800 A. U.

TECHNICAL FIELD OF THE INVENTION

This invention relates to a catalyst for the polymerization of olefins.

TECHNICAL BACKGROUND

A catalyst component for the polymarization of α-olefins, comprisingmagnesium or a metal oxide and magnesium, titanium, a halogen and anelectron-donating compound is known. This catalyst of the metal oxidesupport type has jointly good polymerization properties such as highactivity and high stereoregularity and excellent grain propertieswhereby polymers are obtained having narrow grain size distributions anduniform grain forms.

When the grain strength of a catalyst component is low, a polymer formedby polymerization is broken to give a fine powder. As a typical methodfor preventing this phenomenon, there is a so-called previouspolymerization method comprising previously contacting the catalystcomponent with an olefin to take the thus formed polymer in the catalystand thereby increasing the strength of the catalyst component. It hasbeen proposed to improve the grain strength and increase thestereoregularity of the poly α-olefin by adding an electron-donatingcompound such as silane compounds during the previous polymerization.

However, the addition of an electron-donating compound during theprevious polymerization ordinarily has influences such as lowering ofthe catalyst activity and deterioration of the properties during storageof the catalyst. As the silane compound to be added during the previouspolymerization, there are often used compounds having aromatic groupsfrom the standpoint of the properties, but depending on the object ofusing the polymer, the silane compounds having aromatic groups areharmful in some cases.

The inventors have made various studies for the purpose of increasingthe strength of catalyst grains, improving the stereoregularity of theresulting polymer, maintaining the high activity of the catalyst andpreventing the catalyst from deterioration of the property thereofduring storage and consequently, have found that when using a dimethoxysilane-containing compound having a volume of 170 to 500Å³, inparticular, 230 to 500Å³ and an electron density of oxygen in themethoxy group, ranging from 0.685 to 0.800 A. U., in particular, 0.690to 0.800 A. U., as a silane compound to be added during previouspolymerization, poly α-olefins can be obtained with properties, atleast, comparable to those obtained when using organosilicone compoundshaving aromatic groups, and the object of the present invention can thusbe achieved.

DISCLOSURE OF THE INVENTION

That is, the gist of the present invention consists in a catalystcomponent for the polymerization of α-olefins (hereinafter referred toas first invention) obtained by contacting (A) a solid componentcomprising, as essential components, magnesium, titanium, a halogen andan electron-donating compound with (D) an olefin in the presence of (B)a trialkylaluminum and (C) a dimethoxy group-containing compoundrepresented by the general formula R¹ R² Si (OCH₃)₂ where R¹ and R² are,same or different, aliphatic hydrocarbon groups with 1 to 10 carbonatoms and having a volume, calculated by the quantum chemistrycalculation, of 230 to 500Å³ and an electron density of oxygen atoms inthe methoxy group, calculated similarly, ranging from 0.685 to 0.800 A.U. (atomic unit) and a catalyst component for the polymerization ofα-olefins (hereinafter referred to as second invention) obtained bycontacting (A) a solid component comprising, as essential components, ametal oxide, magnesium, titanium, a halogen and an electron-donatingcompound with (D) an olefin in the presence of (B) a trialkylaluminumand (C) a dimethoxy group-containing compound represented by the generalformula R¹ R² Si (OCH₃)₂ where R¹ and R² are, same or different,aliphatic hydrocarbon groups with 1 to 10 carbon atoms and having avolume, calculated by the quantum chemistry calculation, of 170 to 500Å³and an electron density of oxygen atoms in methoxy group, calculatedsimilarly, ranging from 0.690 to 0.800 A. U. (atomic unit) or the volumein the range of 200 to 500Å and the electron density in the range of0.685 to 0.800 A. U.

SOLID COMPONENT

A solid component (Component A) used in the present invention comprises,as essential components, magneisum or a metal oxide and magnesium,titanium, a halogen and an electron-donating compound, and canordinarily be prepared by contacting a metal oxide, magnesium compound,titanium compound and electron-donating compound, optionally with ahalogen-containing compound in a case where each of these compounds isfree from halogens.

(1) Metal Oxides

The metal oxide used in the second invention includes oxides of Group IIto IV elements of Periodic Table, for example, B₂ O₃, MgO, Al₂ O₃, SiO₂,CaO, TiO₂, ZnO, ZrO₂ SnO₂, BaO, ThO₂, etc. Above all, B₂ O₃, MgO, Al₂O₃, SiO₂, TiO₂ and ZrO₂ are preferably used and in particular, SiO₂ ismost preferable. Furthermore, there can be used composite oxidescontaining these metal oxides can be used, for example, SiO₂ -MgO, SiO₂-Al₂ O₃, SiO₂ -TiO₂, SiO₂ -V₂ O₅. SiO₂ -Cr₂ O₃ and SiO₂ -TiO₂ -MgO.

These metal oxides can ordinarily be used in the form of powder. Sincethe size and shape of the powder often affects those of the resultingpolymer, it is desired to suitably control them. Preferably, the metaloxides are calcined at a high temperature as more as possible so as toremove harmful materials before use and handled not so as to be incontact with the air.

(2) Magnesium Compounds

The magnesium compound is represented by the general formula MgR¹ R²wherein R¹ and R² are, same or different, hydrocarbon groups, OR groupswherein R is a hydrocarbon group, or halogen atoms. Specifically, thehydrocarbon groups of R¹ and R² include alkyl, cycloalkyl, aryl andaralkyl groups containing 1 to 20 carbon atoms and R of the OR groupsinclude alkyl, cycloalkyl, aryl and aralkyl groups containing 1 to 12carbon atoms. The halogen atoms are chlorine, bromine, iodine andfluorine.

Examples of these compounds are shown in the following, in which Me:methyl; Et: ethyl; Pr: propyl; Bu: butyl; He: hexyl; Oct: octyl; Ph:phenyl; and cylle: cyclohexyl.

MgMe₂, MgEt₂, Mgi-Pr₂, MgBu₂, MgHe₂, MgOct₂, MgEtBu, MgPh₂, MgcyHe₂,Mg(OMe)₂, Mg(OEt)₂, Mg(OBu)₂, Mg(OHe)₂, Mg(OOct)₂, Mg(OPh)₂, Mg(OcyHe)₂,EtMgCl, BuMgCl, HeMgCl, i-BuMgCl, t-BuMgCl, PhMgCl, PhCH₂ MgCl, EtMgBr,BuMgBr, PhMgBr, BuMgI, EtOMgCl, BuOMgCl, HeOMgCl, PhOMgCl, EtOMgBr,BuOMgBr, EtOMgI, MgCl₂, MgBr₂ and MgI₂.

The above described magnesium compounds can also be prepared frommetallic magnesium or other magnesium compounds when Component A isprepared. For example, there is a method comprising contacting metallicmagnesium, a halogenated hydrocarbon and an alkoxy group-containingcompound represented by the general formula X_(n) M(OR)_(m-n) in which Xis a hydrogen atom, a halogen atom or a hydrocarbon group of 1 to 20carbon atoms, M is boron, carbon, aluminum, silicon or phosphorus, R isa hydrocarbon of 1 to 20 carbon atoms, m is the atomic valence of M andm>n ≧0. The hydrocarbon group of X or R in the general formula of thealkoxy group-containing compound includes alkyl groups such as methyl(Me), ethyl (Et), propyl (Pr), i-propyl (i-Pr), butyl (Bu), i-butyl(i-Bu), hexyl (He), octyl groups (Oct) and the like; cycloalkyl groupssuch as cyclohexyl (cyHe), methylcyclohexyl groups and the like; alkenylgroups such as allyl, propenyl, butenyl groups and the like; aryl groupssuch as phenyl, tolyl, xylyl groups and the like; and aralkyl groupssuch as phenethyl, 3-phenylpropyl groups and the like. Above all, analkyl groups containing 1 to 10 carbon atoms is preferably used. Thealkoxy group-containing compound is exemplified as follows:

1 Compound when M is carbon

C(OR)₄ such as C(OMe)₄, C(OEt)₄, C(OPr)₄, C(OBu)₄, C(Oi-Bu)₄, C(OHe)₄and C(OOct)₄ : XC(OR)₃ such as HC(OMe)₃, HC(OEt)₃, HC(OPr)₃, HC(OBu)₃,HC(OHe)₃, HC(OPh)₃, MeC(OMe)₃, MeC(OEt)₃, EtC(OMe)₃, EtC(OEt)₃,cyHeC(OEt)₃, PhC(OMe)₃, PhC(OEt)₃, CH₂ ClC(OEt)₃, MeCHBrC(OEt)₃,MeCHClC(OEt)₃, ClC(OMe)₃, ClC(OEt)₃, ClC(Oi-Bu)₃, and BrC(OEt)₃ ; X ₂C(OR)₂ such as MeCH(OMe)₂, MeCH(OEt)₂, CH₂ (OMe)₂, CH₂ (OEt)₂, CH₂ClCH(OEt)₂, CHCl₂ CH(OEt)₂ CCl₃ CH(OEt)₂, CH₂ BrCH(OEt)₂ and PhCH(OEt)₂.

2 Compound when M is silicon

Si(OR)₄ such as Si(OMe)₄, Si(OEt)₄, Si(OBu)₄, Si(Oi-Bu)₄, Si(OHe)₄,Si(OOct)₄ and Si(OPh)₄ ; XSi(OR)₃ such as HSi(OEt)₃, HSi(OBu)₃,HSi(OHe)₃ HSi(OPh)₃, MeSi(OMe)₃, MeSi(OEt)₃, MeSi(OBu)₃, EtSi(OEt)₃,PhSi(OEt)₃, EtSi(OPh)₃, ClSi(OMe)₃, ClSi(OEt)₃, ClSi(OBu)₃, ClSi(OPh)₃,and BrSi(OEt)₃ ; X₂ Si(OR)₂ such as Me₂ Si(OMe)₂, Me₂ Si(OEt)₂, Et₂Si(OEt)₂, MeClSi(OEt)₂, CHCl₂ SiH(OEt)₂, CCl₃ SiH(OEt)₂ and MeBrSi(OEt)₂; X₃ SiOR such as Me₃ SiOMe, Me₃ SiOEt, Me₃ SiOBu, Me₃ SiOPh, Et₃ SiOEtand Ph₃ SiOEt.

3 Compound when M is boron

B(OR)₃ such as B(OEt)₃, B(OBu)₃, B(OHe)₃ and B(OPh)₃.

4 Compound when M is aluminum

Al(OR)₃ such as Al(OMe)₃, Al(OEt)₃, Al(OPr)₃, Al(Oi-Pr)₃, Al(OBu)₃,Al(Ot-Bu)₃, Al(OHe)₃ and Al(OPh)₃.

5 Compound when M is phosphorus

P(OR)₃ such as P(OMe)₃, P(OEt)₃, P(OBu)₃, P(OHe)₃ and P(OPh)₃.

As the above described magnesium compound, there can be used complexeswith organic compounds of Group II or IIIa metals (M) of Periodic Table,which are represented by the general formula MgR¹ R².n(MR³ _(m)) whereinM is aluminum, zinc, calcium, etc., R³ is an alkyl group, cycloalkylgroup, aryl group or aralkyl group containing 1 to 12 carbon atoms, m isthe atomic valence of M and n is a numeral of 0.1 to 10. Examples of thecompound represented by MR³ _(m) are AlMe₃, AlEt₃, Ali-Bu₃, AlPh₃,ZnMe₂, ZnEt₂, ZnBu₂, ZnPh₂, CaEt₂, CaPh₂ and the like.

(3) Titanium Compound

The titanium compound includes compounds of di-, tri- and tetravalenttitanium, illustrative of which are titanium tetrachloride, titaniumtetrabromide, trichoroethoxytitanium, trichlorobutoxytitanium,dichlorodiethoxytitanium, dichlorodibutoxytitanium,dichlorodiphenoxytitanium, chlorotriethoxytitanium,chlorotributoxytitanium, tetrabutoxytitanium, titanium trichloride andthe like. Above all, halides of tetravalent titanium such as titaniumtetrachloride, trichloroethoxytitanium, dichlorodibutoxytitanium,dichlorodiphenoxytitanium, etc. are preferable and in particular,titanium tetrachloride is most preferable.

(4) Electron-donating Compounds

As the electron donating compound, there are given carboxylic acids,carboxylic acid anhydride, carboxylic acid esters, carboxylic acidhalides, alcohols, ethers, ketones, amines, amides, nitriles, aldehydes,alcolates, phosphorus, arsenic and antimony compounds bonded withorganic groups through carbon or oxygen, phosphonamides, thioethers,thioesters, carbonic acid esters and the like. Above all, it ispreferable to use the carboxylic acids, carboxylic acid anhydrides,carboxylic acid esters, carboxylic acid halides, alcohols, ethers, etc.

Examples of the carboxylic acid are aliphatic monocarboxylic acids suchas formic acid, acetic acid, propionic acid, butyric acid, isobutyricacid, valeric acid, caproic acid, pivalic acid, acrylic acid,methacrylic acid, crotonic acid and the like; aliphatic dicarboxylicacids such as malonic acid, succinic acid, glutaric acid, adipic acid,sebacic acid, maleic acid, fumaric acid and the like; aliphaticoxycarboxylic acids such as tartaric acid; alicyclic carboxylic acidssuch as cyclohexanemonocarboxylic acid, cyclohexenemonocarboxylic acid,cis-1,2-cyclohexanedicarboxylic acid,cis-4-methylcyclohexene-1,2-dicarboxylic acid and the like; aromaticmonocarboxylic acids such as benzoic acid, toluic acid, anisic acid,p-t-butylbenzoic acid, naphthoic acid, cinnamic acid and the like; andaromatic polybasic carboxylic acids such as phthalic acid, isophthalicacid, terephthalic acid, napthalic acid, trimellitic acid, hemimelliticacid, trimesic acid, pyromellitic acid, mellitic acid and the like.

As the carboxylic acid anhydride, there can be used the anhydrides ofthe above described carboxylic acids.

As the carboxylic acid ester, there can be used mono- or polyvalentesters of the above described carboxylic acids, illustrative of whichare butyl formate, ethyl acetate, butyl acetate, isobutyl isobutyrate,propyl pivalate, isobutyl pivalate, ethyl acrylate, methyl methacrylate,ethyl methacrylate, isobutyl methacrylate, diethyl malonate, diisobutylmalonate, diethyl succinate, dibutyl succinate, diisobutyl succinate,diethyl glutarate, dibutyl glutarate, diisobutyl glutarate, diisoutyladipate, dibutyl sebacate, diisobutyl sebacate, diethyl maleate, dibutylmaleate, diisobutyl maleate, monomethyl fumarate, diethyl fumarate,diisobutyl fumarate, diethyl tartarate, dibutyl tartarate, diisobutyltartarate, ethyl cyclohexanecarboxylate, methyl benzoate, ethylbenzoate, methyl p-toluiate, ethyl p-tert-butylbenzoate, ethylp-anisate, ethyl α-naphthoate, isobutyl α-naphthoate, ethyl cinnamate,monomethyl phthalate, monobutyl phthalate, dibutyl phthalate, diisobutylphthalate, dihexyl phthalate, dioctyl phthalate, di-2-ethylhexylphthalate, diallyl phthalate, diphenyl phthalate, diethyl isophthalate,diisobutyl isophthalate, diethyl terephthalate, dibutyl terephthalate,diethyl naphthalate, dibutyl naphthalate, triethyl trimellitate,tributyl trimellitate, tetramethyl pyromellitate, tetraethylpyromellitate, tetrabutyl pyromellit ate and the like.

As the carboxylic acid halide, there can be used acid halides of theabove described carboxylic acids, illustrative of which are acetylchloride, acetyl bromide, acetyl iodide, propionyl chloride, butyrylchloride, butyryl bromide, butyryl iodide, pivalyl chloride, pivalylbromide, acrylyl chloride, acrylyl bromide, acrylyl iodide, methacryloylchloride, methacryloyl bromide, methacrylyl iodide, crotonyl chloride,malonyl chloride, malonyl bromide, succinyl chlride, succinyl bromide,glutaryl chloride, glutaryl bromide, adipyl chloride, adipyl bromide,sebacoyl chloride, sebacoyl bromide, maleoyl chloride, maleoyl bromide,fumaryl chloride, fumaryl bromide, tartaryl chloride, tartaryl bromide,cyclohexancarboxylic chloride, cyclohexanecarboxylic bromide,1-cyclohexenecarboxylic chloride, cis-4-methylcyclohexenecarboxylicchloride, cis-4-methylcyclohexenecarboxylic bromide, benzoyl chloride,benzoyl bromide, p-toluoyl chloride, p-toluoyl bromide, p-anisoylchloride, p-anisoyl bromide, α-naphthoyl chloride, cinnamoyl chloride,cinnamoyl bromide, phthaloyl dichloride, phthaloyl dibromide,isophthaloyl dichloride, isophthaloyl dibromide, terephthaloyldichloride, naphthaloyl dichloride and the like. Monoalkylhalides ofdicarboxylic acids can also be used such as adipyl monomethylchloride,maleoyl monoethylchloride, phthaloyl butylchloride can also be used.

Alcohols are represented by the general formula ROII wherein R is analkyl, alkenyl, cycloalkyl, aryl or aralkyl group containing 1 to 12carbon atoms. Examples of the alcohol are methanol, ethanol, propanol,isopropanol, butanol, isobutanol, pentanol, hexanol, octanol,2-ethylhexanol, cyclohexanol, benzyl alcohol, allyl alcohol, phenol,cresol, xylenol, ethylphenol, isopropylphenol, p-tert-butylphenol,n-octylphenol and the like.

Ethers are represented by the general formula ROR¹ wherein R and R¹ arealkyl, alkenyl, cycloalkyl, aryl and aralkyl groups containing 1 to 12carbon atoms, R and R¹ being same or different. Examples of the ethersare diethyl ether, diisopropyl ether, dibutyl ether, diisobutyl ether,diisoamyl ether, di-2-ethylhexyl ether, diallyl ether, ethyl allylether, butyl allyl ether, diphenyl ether, anisole, ethyl phenyl etherand the like.

Preparation of Component A is carried out by methods comprising 1contacting a magnesium compound (Component 1), titanium compound(Component 2) and electron-donating compound (Component 3) in thisorder, 2 contacting Components 1 and 3 and then contacting withComponent 2, and 3 simultaneously contacting Components 1,2 and 3.Before contacting with Component 2, a halogen-containing compound can becontacted.

Preparation of Component A can also be carried out by other methodscomprising 1 contacting a metal oxide (Component 1), magnesium compound(Compound 2), titanium compound (Component 3) and electron-donatingcompound (Component 4) in this order, 2 contacting Components 1 and 2and then contacting with Component 3 and Component 4 in order, 3contacting Components 1 and 2 and then contacting with Components 3 and4 simultaneously, 4 contacting Components 2 and 3 and then withComponent 4 and Component 1 in this order, 5 contacting Components 2 and4 and then contacting with Component 3 and Component 1 in this order,and 6 simultaneously contacting Components 2, 3 and 4 and thencontacting with Component 1. Before contacting with Component 3, ahalogen-containing compound can be contacted.

As the halogen-containing compound, there can be used halogenatedhydrocarbons, halogen-containing alcohols, halogenated silicon compoundshaving hydrogen-silicon bonds and halides of Group IIa, IVa and Vaelements of Periodic Table (which will hereinafter be referred to asmetal halides).

As the halogenated hydrocarbon, there can be used mono- andpoly-halogen-substitued products of saturated or unsaturated aliphatic,alicyclic and aromatic hydrocarbons containing 1 to 12 carbon atoms.Examples of these compounds are aliphatic compounds such as methylchloride, methyl bromide, methyll iodide, methylene chloride, methylenebromide, methylene iodide, choroform, bromoform, iodoform, carbontetrachloride, carbon tetrabromide, carbon tetraiodide, ethyl chloride,ethyl bromide ethyl iodide, 1,2-dichloroethane, 1,2-dibromoethane,1,2-diiodoethane, methylchloroform, methylbromoform, methyliodoform,1,1,2-trichloroethylene, 1,1,2-tribromoethylene,1,1,2,2-tetrachloroethylene, pentachloroethane, hexachloroethane,hexabromoethane, n-propyl chloride, 1,2-dichloropropane,hexachloropropylene, octachloropropane, decabromobutane and chlorinatedparaffins; alicyclic compounds such as chlorocyclopropane,tetrachlorocyclopentane, hexachlorocyclopentadiene andhexachlorocyclohexane; and aromatic compounds such as chlorobenzene,bromobenzene, o-dichlorobenene, p-dichlorobenzene, hexachlorobenzne,hexabromobenzene, benzotrichloride p-chlorobenzotrichloride and thelike. These compounds can be used individually or in combination.

The halogen-containing alcohol used in the present invention means sucha compound that in a mono- or polyhydric alcohol having one or morehydroxyl groups in one molecule, any one or more hydrogen atoms otherthan the hydroxyl groups are substituted by halogen atoms. As thehalogen atom, there are chlorine, bromine, iodine and fluorine atoms,but chlorine atom is preferable.

Examples of these compounds are 2-chloroethanol, 1-chloro-2-propanol,3-chloro-1-propanol, 1-chloro-2-methyl-2-propanol, 4-chloro-1-butanol,5-chloro-1-pentanol, 6-chloro-1-hexanol, 3-chloro-1,2-propane diol,2-chlorocyclohexanol, 4-chlorobenzhydrol, (m, o, p)-chlorobenzylalcohol, 4-chlorocatechol, 4-chloro-(m, o)-cresol, 6-chloro-(m,o)-cresol, 4-chloro-3,5-dimethylphenol, chlorohydroquinone,2-benzyl-4-chlorophenol, 4-chloro-1-naphthol, (m, o, p)-chlorophenol,p-chloro-α-methyl benzyl alcohol, 2-chloro-4-phenylphenol,6-chlorothymol, 4-chlororesorcin, 2-bromoethanol, 3-bromo-1-propanol,1-bromo-2-propanol, 1-bromo-2-butanol, 2-bromo-p-cresol,1-bromo-2-napthol, 6-bromo-2-naphthol, (m, o, p)-bromophenol,4-bromoresorcin, (m, o. p)-chlorophenol, p-iodophenol,2,2-dichloroethanol, 2,3-dichloro-1-propanol, 1,3-dichloro-2-propanol,3-chloro-1-(α-chloromethyl)-1-propanol, 2,3-dibromo-1-propanol,1,3-dibromo-2-propanol, 2,4-dibromophenol, 2,4-dibromo-1-naphthol,2,2,2-trichloroethanol, 1,1,1-trichloro-2-propanol,βββ-trichloro-tert-butanol, 2,3,4-trichlorophenol,2,4,5-trichlorophenol, 2,4,6-trichlorophenol, 2, 4,6-tribromophenol,2,3,5-tribromo-2-hydroxytoluene, 2,3,5-tribromo-4-hydroxytoluene,2,2,2-trifluoroethanol, ααα-trifluoro-m-cresol, 2,4,6,-triiodophenol,2,3,4,6-tetrachlorophenol, tetrachlorohydroquinone, tetrachlorobisphenolA, tetrabromobisphenol A, 2,2,3,3-tetrafluoro-1-propanol,2,3,5,6-tetrafluorophenol, tetrafluororesorcin and the like.

As the halogenated silicon compound having hydrogen-silicon bonds, therecan be used IISiCl₃, II₂ SiCl₂, II₃ SiCl, IICII₃ SiCl₂, IIC₂ II₅ SiCl₂,II(t-C₄ II₉)SiCl₂, IIC₆ II₅ SiCl₂, II(CII₃)₂ SiCl, II(i-C₃ II₇)₂ SiCl,II₂ C₂ II₅ SiCl, II₂ (n-C₄ II₉)SiCl, II₂ (C₆ II₄ CII₃)SiCl, IISiCl(C₆II₅)₂ and the like.

As the metal halide, there can be used chlorides, fluorides, bromidesand iodides of B, Al, Ga, In, Tl, Si, Ge, Sn, Pb, As, Sb and Bi. Inparticular, BCl₃, BBr₃, BI₃, AlCl₃, AlBr₃, GaCl₃, GaBr₃, InCl₃, TlCl₃,SiCl₄, SnCl₄, SbCl₅, SbF₅ and the like are preferable.

Contacting of Components 1, 2 and 3 or Components 1, 2, 3 and 4optionally with a halogen-containing compound to be contacted is carriedout by mixing and stirring or mechanically co-pulverizing in thepresence or absence of an inert medium while heating at 40° to 150° C.As the inert medium, there can be used saturated aliphatic hydrocarbonssuch as hexane, heptane, octane, etc., saturated alicyclic hydrocarbonssuch as cyclopentane, cyclohexane, etc. and aromatic hydrocarbons suchas benzene, toluene, xylene, etc.

Preparation of Component A in the present first invention is preferablycarried out by methods disclosed in Japanese Patent Laid-OpenPublication Nos. 264607/1988, 198503/1983 and 146904/1987.

That is, 1 Japanese Patent Laid-Open Publication No. 264607/1988discloses a method comprising contacting (a) metallic magnesium, (b) ahalogenated hydrocarbon and (c) a compound represented by the generalformula X_(n) M(OR)_(m-n) (same as the foregoing alkoxy group-containingcompounds) to obtain a magnesium-containing solid, contacting this solidwith (d) a halogen-containing alcohol and then contacting with (e) anelectron-donating compound and (f) a titanium compound, 2 JapanesePatent Laid-Open Publication No. 146904/1987 discloses a methodcomprising contacting (a) a magnesium dialkoxide and (b) a halogenatedsilicon compound having hydogen-silicon bonds, contacting with (c) ahalogenated titanium compound and contacting with (d) anelectron-donating compound (if necessary, further contacting with thehalogenated titanium compound) and 3 Japanese Patent Laid-OpenPublication No. 198503/1983 discloses a method comprising contacting (a)a magnesium dialkoxide and (b) a halogenated silicon compound havinghydrogen-silicon bonds, then contacting with (c) an electron-donatingcompound and then contacting with (d) a titanium compound. Above all,the method 1 is most preferable.

Preparation of Component A in the present second invention is preferablycarried out by methods disclosed in Japanesse Patent Laid-OpenPublication Nos. 162607/1983, 94909/1980, 115405/1980, 108107/1982,21109/1986, 174204/1986, 174205/1986, 174206/1986 and 7706/1987.

1 Japanese Patent Laid-Open Publication No. 162607/1983 discloses amethod comprising contacting a reaction product of a metal oxide andmagnesium dialkoxide with an electron-donating compound and atetravalent titanium halide, 2 Japanese Patent Laid-Open Publication No.94909/1980 discloses a method contacting a reaction product of a metaloxide and magnesium hydrocarbylhalide with a Lewis base compound andtitanium tetrachloride, 3 Japanese Patent Laid-Open Publication Nos.115405/1980 and 108107/1982 discloses a method comprising contacting anelectron-donating compound and a halogenated silicon compound beforecontacting a titanium compound with a reaction product of a poroussupport such as silica and a alkylmagnesium compound, 4 Japanese PatentLaid-Open Publication No. 174204/1986 discloses a method comprisingcontacting a metal oxide, an alkoxy group-containing magnesium compound,an aromatic polybasic carboxylic acid having carboxylic group at theorthoposition or its derivative and a titanium compound, 5 JapanesePatent Laid-Open Publication No. 174205/1986 discloses a methodcomprising contacting a metal oxide, an alkoxy group-containingmagnesium compound, a silicon compound having hydrogen-silicon bonds, anelectron-donating compound and a titanium compound, 6 Japanese PatentLaid-Open Publication No. 174206/1986 discloses a method comprisingcontacting a metal oxide, alkoxy group-containing magnesium compound,halogen element or halogen-containing compound, electron-donatingcompound and titanium compound, 7 Japanese Patent Laid-Open PublicationNo. 21109/1986 discloses a method comprising contacting a metal oxide,dihydrocarbylmagnesium and halogen-containing alcohol to obtain areaction product and then contacting the reaction product with anelectron-donating compound and titanium compound and 8 Japanese PatentLaid-Open Publication No. 7706/1987 discloses a method comprisingcontacting a metal oxide, hydrocarbylmagnesium and hydrocarbyloxygroup-containing compound (corresponding to the foregoing alkoxygroup-containing compound) to obtain a solid and then contacting thesolid with a halogen-containing alcohol and further with anelectron-donating compound and titanium compound. Above all, the methods4 to 8 are preferable and in particular, the methods 7 and 8 are mostpreferable.

Component A is thus prepared, but if necessary, Component A can bewashed with an inert medium as described above and dried.

TRIALKYLALUMINUM

Trialkylaluminum (which will hereinafter be referred to as Component B)is represented by the general formula AIR₃ wherein R is an alkyl grouphaving 1 to 12 carbon atoms, examples of which are trimethylaluminum,triethylaluminum, tripropylaluminum, triisopropylaluminum,tributylaluminum, triisobutylaluminum, trihexylaluminum, etc.

DIMETHOXY GROUP-CONTAINING SILANE COMPOUND

The dimethoxy group-containing silane compound (which will hereinafterbe referred to as Component C) used in the present first invention isrepresented by the general formula R¹ R² Si(OCII₃)₂ and has a molecularvolume of 230 to 500Å³ and an electron density of oxygen atoms in themethoxy group of 0.685 to 0.800 A.U. (atomic unit), calculated by thequantum chemistry.

The dimethoxy group-containing silane compound (which will hereinafterbe referred to as Component C) used in the present second invention isrepresented by the general formula R¹ R² Si(OCII₃)₂ and has a molecularvolume of 170 to 500Å³ and an electron density of oxygen atoms in themethoxy group of 0.690 to 0.800 A.U. (atomic unit), calculated by thequantum chemistry, or has the volume of 200 to 500Å³ and the electrondensity of 0.685 to 0.800 A.U.

The quantum chemistry calculation is effected as follows:

The molecular volume is obtained by the MNDO method [a kind ofsemi-empirical molecular orbital method, J.Am.Chem.Soc. 99, page 4899,page 4907 (1977), ibid 100, page 3607 (1978)] of MOPAC as a program ofthe molecular orbital method [bought from QCPE (Quantum ChemistryProgram Organization) as a non-profit-making organization for spreadingvarious programs for chemistry in the Indiana University, USA] and theVan der Waals Radius [J.Phys.Chem. 68, page 441-451 (1964)]. Theelectron density of oxygen atoms in the methoxy group is calculated bythe MNDO method of MOPAC as described above. For this calculation, VAX11/785 manufactured by DEC (Degital Equipment Corporation) was used.

R¹ and R² in the foregoing general formula for Component C are aliphatichydrocarbon groups having 1 to 10 carbon atoms, that is, alkyl groupsand alkenyl groups, preferably alkyl groups.

Component C in the first invention of the present application has theforegoing molecular volume and electron density of oxygen atoms,preferably a volume of 230 to 350Å³ and an electron density of 0.690 to0.740 A.U.

For Component C capable of satisfying the foregoing volume and electrondensity, it is required that the carbon number of R¹ and R² are 3 to 8and the sum of the carbon number of R¹ and R² is at least 9, preferablythat of R¹ and R² being at least 10.

Examples of Component C are given below by chemical formulas:

In the formula, Me: CH₃ ; Et: C₂ H₅ : Pr: C₃ H₇ ; Bu:C₄ H₉ ; Pt:C₅ H₁₁ ;and He: C₆ H₁₃.

(t-Bu)(t-Pt)Si(OMe)₂, (t-Bu)(s-Pt)Si(OMe)₂, (t-Pt)₂ Si(OMe)₂,[(n-Pr)(Me)CH]₂ Si(OMe)₂, (t-Pt)(s-Pt)Si(OMe)₂, [t-Bu.CH₂ ]₂ Si(OMe)₂,[(Et)(Me)CH.CH₂ ]₂ Si(OMe)₂, (t-Pt)[t-Bu.CH₂ ]₂ Si(OMe)₂. [(n-Pr)(Me)₂C](t-Pt)Si(OMe)₂, [(Et)(Me)₂ C.CH₂ ](t-Pt)Si(OMe)₂, (n-He)₂ Si(OMe)₂,[(n-Pr)(Me)₂ C]₂ Si(OMe)₂, [(Et)(Me)₂ C.CH₂ ]₂ Si(OMe)₂. [t-Bu.C₂ H₄ ]₂Si(OMe)₂, ](n-Pr)(Me)₂ C][(Et)(Me)₂ C. CH₂ ]Si(OMe)₂. etc.

Component C in the present second invention has a volume of 170 to 500Å³and an electron density of oxygen atoms of 0.690 to 0.800 A.U. or avolume of 200 to 500 Å³ and an electron density of oxygen atoms of 0.685to 0.800 A.U. and it is preferable to use one having a volume of 200 to400 Å³ and an electron density of 0.690 to 0.760 A.U., in particular, avolume of 230 to 350 Å³ and an electron density of 0.690 to 0.740 A.U.

For Component C capable of satisfying the foregoing volume and electrondensity, it is required that the sum of the carbon number of R¹ and R²is at least 5, preferably 7, more preferably 9.

Examples of Component C are given below by chemical formulas:

In the formula, Me: CH₃ ;Et: C₂ H₅ : Pr: C₃ H₇ ; Bu:C₄ H₉ ; Pt:C₅ H₁₁ ;and He: C₆ H₁₃.

(t-Bu)(Me)Si(OMe)₂, (i-Pr)₂ Si(OMe)₂, (t-Bu)(Et)Si(OMe)₂,(t-Bu)(i-Pr)Si(OMe)₂, (n-He)(Me)Si(Me)₂, (t-Bu)(Et)Si(OMe)₂,[(n-Pr)(Me)₂ C](Me)Si(OMe)₂, (n-Bu)₂ Si(OMe)₂, (i-Bu)₂ Si(OMe), (s-Bu)₂Si(OMe)₂, (t-Bu)₂ Si(OMe)₂, (t-Pt)(i-Pr)Si(OMe)₂, [(n-Pr)(Me)₂C]Et.Si(OMe)₂, [(Et)₃ C](Me)Si(OMe)₂, (t-Bu)(s-Bu)Si(OMe)₂,(t-Bu)(t-Pt)Si(OMe)₂, [(n-Pr)(Me)₂ C](i-Pr)Si(OMe)₂, [(Et)₃ C](Et)Si(OMe)₂, (t-Bu)[(n-Pr)(Me)CH]Si(OMe)₂, (t-Pt)₂ Si(OMe)₂,[(n-Pr)(Me)CH]₂ Si(OMe)₂, [(Me)₃ C.CH₂ ]₂ Si(OMe)₂, [(Et)(Me)₂ C.CH₂ ]₂Si(OMe)₂, (n-He)₂ Si(OMe)₂, [(Me)₃ C.C₂ H₄ ]₂ Si(OMe)₂, [(Et)(Me)₂ C.CH₂ ]₂ Si(OMe)₂, [(n-Pr)(Me)₂ C]₂ Si(OMe)₂, etc.

PREVIOUS POLYMERIZATION

Previous polymerization of the solid component (Component A) is carriedout by contacting with an olefin in the presence of an trialkyl-aluminumcompound (Component B) and a dimethoxy group-containing silane compound(Component C).

As the olefin, there can be used, in addition to ethylene, α-olefinssuch as propylene, 1-butene, 1-hexene, 4-methyl-1-pentene and the like.

The previous polymerization is preferably carried out in the presence ofan inert medium as described above. The previous polymerization isgenerally carried out at a temperature of at most 100° C., preferably-30° C. to +30° C., more preferably -20° C. to +15° C. Thepolymerization can be carried batchwise or continuously, or in two ormore stages. In the case of carrying out the polymerization inmulti-stage, the polymerization conditions are of course variedcorrespondingly.

Component B is generally used in such a manner that the concentration inthe previous polymerization system is 50 to 500 millimols/1, preferably80 to 200 millimols/1 and 4 to 50,000 mols, preferably 6 to 1,000 molsper 1 gram atom of titanium.

Component C is generally used in such a manner that the concentration inthe previous polymerization is 1 to 100 millimols/1, preferably 5 to 50millimols/1.

The olefin polymer is taken in Component A by the previouspolymerization and the quantity of the polymer is preferably 0.1 to 200g, in particular, 0.5 to 50 g per 1 g of Component A.

The catalyst component of the present invention, prepared in this way,can be diluted or washed with the foregoing inert medium, but from thestandpoint of preventing the catalyst component from deteriorationduring storage, it should preferably be washed. After washing, it can bedried if necessary. When the catalyst component is stored, thetemperature during the same time should preferably be as lower aspossible, that is, -50° C. to +30° C., in particular, -20° C. to +5° C.

POLYMERIZATION OF α-OLEFINS

The catalyst component of the present invention, obtained as describedabove, is useful as a catalyst for the homopolymerization of α-olefinshaving 3 to 10 carbon atoms or the copolymeriation thereof with otherolefins or diolefins having 3 to 10 carbon atoms, in combination withorganometal compounds and optionally electron-donating compounds and inparticular, it gives very excellent properties as a catalyst for thehomopolymerization of α-olefins having 3 to 6 carbon atoms, for example,propylene, 1-butene, 4-methyl-1-pentene, 1-hexene, etc., or for therandom or block copolymerization of the above described α-olefins witheach other and/or ethylene.

The organometal compound which can be used in the present inventionincludes organometal compounds of Group I to III metals of PeriodicTable, for example, organic compounds of lithium, magnesium, calcium,zinc and aluminum. Above all, organoaluminum compounds are preferable.

As the organoaluminum compound, there are used those represented by thegeneral formula R_(n) AIX_(3-n) wherein R is an alkyl or aryl group, Xis a halogen atom, alkoxy group or hydrogen atom and n is any numeral inthe range of 1≦n≦3, for example, alkylaluminum compounds containing 1 to18 carbon atoms, preferably 2 to 6 carbon atoms, such astrialkylaluminum, dialkylaluminum monohalide, monoalkylaluminumdihalide, alkylaluminum sesquihalide and dialkylaluminum monoalkoxide,mixtures or complex compounds thereof. Specifically, there aretrialkylaluminums such as trimethylaluminum, trtiethylaluminum,tripropylaluminum, triisobutylaluminum, trihexylluminum, etc.,dialkylaluminum monohalides such as dimethylaluminum chloride,diethylaluminum chloride, diethylaluminum bromide, diethylaluminumiodide, diisobutylaluminum chloride, etc., monoalkylaluminum dihalidessuch as methylaluminum dichloride, ethylaluminum dichloride,methylaluminum dibromide, ethylaluminum dibromie, ethylaluminumdiiodide, isobutylaluminum dichloride, etc., alkylaluminum sesquihalidesuch as ethylaluminum sesquichloride, etc., dialkyl-aluminummonoalkoxide such as dimethylaluminum methoxide, diethylaluminumethoxide, diethylaluminum phenoxide, dipropylaluminum ethoxide,diisbutylaluminum ethoxide, diisobutylaluminum phenoxide, etc. anddialkylaluminum hydrides such as dimethylaluminum hydride,diethylaluminum hydride, dipropylaluminum hydride, diisobutylaluminumhydride, etc. Above all, trialkylaluminums, particularly,triethylaluminum and triisobutylaluminum are preferable. Thesetrialkylaluminums can be used jointly with other organoaluminumcompounds, for example, commercially available diethylaluminum chloride,ethylaluminum dichloride, ethylaluminum sesquichloride, diethylaluminumethoxide, diethylaluminum hydride or mixtures or complex compoundsthereof.

Furthermore, such an organoaluminum compound that two or more aluminumsare bonded via oxygen atom or nitrogen atom can be used, illustrative ofwhich are (C₂ H₅)₂ AIOAI(C₂ H₅)₂, (C₄ H₉)₂ AIOAI(C₄ H₉)₂ and ##STR1##

As organic compounds of other metals than aluminum metal, there arediethylmagnesium, ethylmagnesium chloride, diethylzinc and compoundssuch as LiAl(C₂ H₅)₄, LiAl(C₇ H₁₅)₄, etc.

As the electron-donating compound which can optionally be combined withthe catalyst component and organometal compound according to the presentinvention, there can be used the foregoing compounds used for thepreparation of Component A and the foregoing silane compounds (ComponentC) used in the previous polymerization. Furthermore, it is also possibleto use electron-donating compounds comprising other organosiliconcompounds than the foregoing silane compounds and electron-donatingcompounds containing hetero atoms such as nitrogen, sulfur, oxygen,phosphorus, etc.

Examples of the organosilicon compound are tetramethoxysilane,tetraethoxysilane, tetrabutoxysilane, tetraisobutoxysilane,tetraphenoxysilane, tetra(p-methylphenoxy)silane, tetrabenzyloxysilane,methyltrimethoxysilane, methyltriethoxysilane, methyltributoxysilane,methyltriphenoxysilane, ethyltriethoxysilane, ethyltriisobutoxysilane,ethyltriphenoxysilane, butyltrimethoxysilane, butyltriethoxysilane,butyltributoxysilane, butyltriphenoxysilane, isobutyltriisobutoxysilane,vinyltriethoxysilane, allyltrimethoxysilane, dimethyldiisopropoxysilane,dimethyldibutoxysilane, dimethyldihexyloxysilane,dimethyldiphenoxysilane, diethyldiethoxysilane,diethyldiisobutoxysilane, diethyldiphenoxysilane,dibutyldiisopropoxysilane, dibutyldibutoxysilane,dibutyldiphenoxysilane, diisobutyldiethoxysilane,diisobutyldiisobutoxysilane, diphenyldimethoxysilane,diphenyldiethoxysilane, diphenyldibutoxysilane, dibenzyldiethoxysilane,divinyldiphenoxysilane, diallyldipropoxysilane,diphenyldiallyloxysilane, methylphenyldimethoxysilane,chlorophenyldiethoxysilane and the like.

Examples of the electron-donating compound containing hetero atoms arecompounds containing nitrogen atoms, such as2,2,6,6-tetramethylpiperidine, 2,6-dimethylpiperidine,2,6-diethylpiperidine, 2,6-diisopropylpiperidine,2,6-diisobutyl-4-methylpiperidine, 1,2,2,6,6-pentamethylpiperidine,2,2,5,5-tetramethylpyrrolidine, 2,5-dimethylpyrrolidine,2,5-diethylpyrrolidine, 2,5-diisopropylpyrrolidine,1,2,2,5,5-pentamethylpyrrolidine, 2,2,5-trimethylpyrrolidine,2-methylpyridine, 3-methylpyridine, 4-methylpyridine,2,6-diisopropylpyridine, 2,6-diisobutylpyridine,1,2,4-trimethylpiperidine, 2,5-dimethylpiperidine, methyl nicotinate,ethyl nicotinate, nicotinamide, benzoic amide, 2-methylpyrrole,2,5-dimethylpyrrole, imidazole, toluic amide, benzonitrile,acetonitrile, aniline, p-toluidine, o-toluidine, m-toluidine,triethylamine, diethylamine, dibutylamine, tetramethylenediamine,tributylamine and the like, compounds containing sulfur atoms, such asthiophenol, thiophene, ethyl 2-thiophenecarboxylate, ethyl3-thiophenecarboxylate, 2-methylthiophene, methylmercatan,ethylmercaptan, isopropylmercaptan, butylmercaptan, diethyl thioether,diphenyl thioether, methyl benzenesulfonate, methyl sulfite, ethylsulfite and the like, compounds containing oxygen atoms, such astetrahydrofuran, 2-methyltetrahydrofuran 3-methyltetrahydrofuran,2-ethyltetrahydrofuran, 2,2,5,5-tetraethyltetrahydrofuran,2,2,5,5-tetraethyltetrahydrofuran, 2,2,6,6-tetraethyltetrahydrofuran,2,2,6,6-tetrahydropyrane, dioxane, dimethyl ether, diethyl ether,dibutyl ether, diisoamyl ether, diphenyl ether, anisole, acetophenone,acetone, methyl ethyl ketone, acetylacetone, o-tolyl-t-butylketone,methyl-2,6-di-t-butylphenylketone, ethyl 2-furalate, isoamyl 2-furalate,methyl 2-furalate, propyl 2-furalate and the like and compoundscontaining phosphorus atoms, such as triphenylphosphine,tributylphosphine, triphenyl phsphite, tribenzyl phophite, diethylphophate, diphenyl phophate and the like.

These electron-donating compounds can be used in combination of two ormore. Furthermore, these electron-donating compounds can be used when anorganometal compound is used in combination with the catalyst componentor after contacted previously with an organometal compound.

The quantity of an organometal compound used for the catalyst componentof the present invention is ordinarily 1 to 2,000 gram moles, inparticular, 20 to 500 gram moles per 1 gram atom of titanium in thecatalyst component.

The ratio of the organometal compound and electron-donating compound is0.1 to 40, preferably 1 to 25 gram atoms, as aluminum, of theorganometal compound to 1 mole of the electron-donating compound.

The polymerization reaction of α-olefins is carried out either ingaseous or liquid phase. In the case of the liquid phase, thepolymerization is carried out in an inert hydrocarbon such as n-butane,i-butane, n-pentane, i-pentane, hexane, heptane, octane, cyclohexane,benzene, toluene, or xylene or in a liquid monomer. The polymerizationtemperature is generally -80° to +150° C., preferably 40° to 120° C. andthe polymerization pressure can be, for example, 1 to 60 atm. Control ofthe molecular weight of the resulting polymer is carried out in thepresence of hydrogen or other known molecular weight regulating agents.

In the copolymerization, the amount of other polyolefins to becopolymerized with α-olefin is generally at most 30% by weight, inparticular, 0.3 to 15% by weight to the α-olefin. The polymerizationreaction is carried out continuously or batchwise under the commonlyused conditions. The copolymerization reaction can be carried out eitherin one or more stages.

EXAMPLES

The present invention will be illustrated specifically by the followingexamples and application examples, in which percents (%) are to be takenas those by weight unless otherwise indicated.

The heptane-insoluble content (hereinafter referred to as III) showingthe proportion of a crystalline polymer in the polymer is a residualamount obtained by extracting the product with boiled n-heptane by meansof a Soxhlet extractor of improved tytpe for 6 hours.

EXAMPLE 1 Preparation of Component A

8.3 g of chipped metallic magnesium (purity 99.5%, average graindiameter 1.6 mm) and 250 ml of n-hexane were charged in a reactor of1000 ml equipped with a refluxing condenser in nitrogen atmosphere andstirred at 68° C. for 1 hour, after which the metallic magnesium wastaken out and dried at 65° C. under reduced pressure, thus obtainingmetallic magnesium.

To this metallic magnesium were then added 140 ml of n-butyl ether and0.5 ml of a solution of n-butylmagnesium chloride in n-butyl ether (1.75mole/l) to prepare a suspension, to which while maintaining at 55° C., asolution of 38.5 ml of n-butyl chloride dissolved in 50 ml of n-butylether was dropwise added in 50 minutes. The reaction was carried outwhile stirring at 70° C. for 4 hours and the reaction solution wasmaintained at 25° C.

55.7 ml of HC(OC₂ H₅)₃ was then dropwise added for 1 hour to thereaction solution, after which the reaction was carried out at 60° C.for 15 minutes and the solid reaction product was washed with 300 ml ofn-hexane 6 times and dried under reduced pressure for 1 hour at roomtemperature, thus obtaining 31.6 g of a magnesium-containing solidcontaining 19.0% of magnesium and 28.9% of chlorine.

6.3 g of the magnesium-containing solid and 50 ml of n-heptane werecharged in a nitrogen gas atmosphere in a reactor of 300 ml equippedwith a refluxing condenser, stirrer and dropping funnel to prepare asuspension, to which a mixed solution of 20 ml (0.02 millimol) of2,2,2-trichloroethanol and 11 ml of n-heptane was dropwise added for 30minutes from the dropping funnel while stirring at room temperature andstirred for 1 hour at 80° C. The thus resulting solid was separated byfiltration, washed 4 times with 100 ml of n-hexane at room temperatureand further washed 2 times with 100 ml of toluene to obtain a solidcomponent.

To the above described solid component were added 40 ml of toluene andtitanium tetrachloride was then added thereto to give a titaniumtetrachloride/toluene volume ratio of 3/2, followed by raising thetemperature to 90° C. Under stirring, a mixed solution of 2 ml ofdi-n-butyl phthalate and 5 ml of toluene was dropwise added thereto for5 minutes and stirred for 2 hours at 120° C. The thus resulting solidmaterial was separated by filtration at 90° C. and washed 2 times with100 ml of toluene at 90° C. Further, titanium tetrachloride was newlyadded to give a titanium tetrachloride/toluene volume ratio of 3/2 andstirred at 120° C. for 2 hours. The resulting solid material wasseparated by filtration at 110° C. and washed 7 times respectively with100 ml of n-hexane at room temperature to obtain 5.5 g of Component A.

Previous Polymerization

2.5 g of Component A, obtained as above, and 280 ml of n-heptane werecharged in a reactor of 500 ml equipped with a stirrer in a nitrogenatmosphere and cooled to -5° C. with agitation. A solution oftriethylaluminum (hereinafter referred to as TEAL) in n-heptane (2.0mols/l) and a solution of di-n-hexyldimethoxysilane in n-heptane (1.0mol/l) were added thereto in such a manner that the concentrations ofTEAL and di-n-hexyldimethoxysilane be respectively 100 millimols/l and10 millimols/l in the reaction system, followed by stirring for 5minutes. Then, after the system was evacuated to 400 mmHg, propylene gaswas continuously fed to the reaction system and polymerized for 30minutes. After the polymerization, the propylene gas of gaseous phasewas purged with nitrogen gas and the solid phase was washed 3 times with100 ml of n-hexane at room temperature. Then, the solid phase was driedunder reduced pressure at room temperature for 1 hour to prepare acatalyst component. When the quantity of magnesium contained in thecatalyst component was measured, the quantity of the previouspolymerization was 2.0 per 1 g of Component A.

Furthermore, the volume of the di-n-hexyldimethoxysilane and theelectron density of oxygen atoms in methoxy groups were calculated asdescribed above to obtain results shown in Table 1.

EXAMPLES 2 TO 5

A catalyst component was prepared by carrying out the previouspolymerization of Component A in an analogous manner to Example 1,except using a silane compound shown in Table 1 instead of thedi-n-hexyldimethoxysilane, TEAL or a trialkylaluminum shown in Table 1instead of TEAL with a concentration shown in Table 1 and previouspolymerization ditions shown in Table 1, in the previous polymerizationof Example 1.

In Table 1 are shown calculated values as to the volume and the electrondensity of oxygen atoms in the methoxy groups of each of the silanecompounds.

COMPARATIVE EXAMPLE 1

A catalyst component was prepared by carrying out the previouspolymerization of Component A in an analogous manner to Example 1,except not using the di-n-hexyldimethoxysilane under the previouspolymerization conditions shown in Table 1, in the previouspolymerization of Example 1.

COMPARATIVE EXAMPLE 2

A catalyst component was prepared by carrying out the previouspolymerization of Component A in an analogous manner to Example 1,except using dimethyldimethoxysilane instead of thedi-n-hexyldimethoxysilane and previous polymerization conditions shownin Table 1 in the previous polymerization of Example 1.

COMPARATIVE EXAMPLE 3

A catalyst component (Component A) was prepared by repeating theprocedure of Example 1, except not carrying out the previouspolymerization.

REFERENCE EXAMPLE 1

A catalyst component was prepared by carrying out the previouspolymerization of Component A in an analogous manner to Example 1,except using diphenyldimethoxysilane instead of thedi-n-hexyldimethoxysilane and the previous polymerization conditionsshown in Table 1.

                                      TABLE 1                                     __________________________________________________________________________                                               Previous Polymerization            Silane Compound                  AlR.sub.3 Tem-    Amount of                                         Electron                                                                           Concen-   Concen-                                                                            per-    Polymer-                   Ex-               Volume                                                                             Density                                                                            tration   tration                                                                            ature                                                                             Time                                                                              ization                                                                             After-               ample                                                                             Formula       (Å.sup.3)                                                                      (A.U.)                                                                             (mmol/l)                                                                           Name (mmol/l)                                                                           (°C.)                                                                      (min)                                                                             (g/g) treatment.sup.2)     __________________________________________________________________________    Ex-                                                                           ample                                                                         1   (n-He).sub.2 Si(OMe).sub.2                                                                  290.4                                                                              0.6941                                                                             10   TEAL 100  -5  30  2.0   wash × 3                                                                times dry            2   [(n-Pr)(Me)CH].sub.2 Si(OMe).sub.2                                                          256.4                                                                              0.6980                                                                              8   TEAL  80  5   30  4.5   dil.sup.3) by 5                                                               times                3   [(Et)(Me).sub.2 C].sub.2 Si(OMe).sub.2                                                      256.4                                                                              0.7223                                                                             10   TEAL 100  0   30  3.2   wash × 1                                                                time                 4   [(Me).sub. 3 C.CH.sub.2 ].sub.2 Si(OMe).sub.2                                               256.2                                                                              0.6934                                                                             10   TIBAL.sup.1)                                                                       100  0   90  10.2  dil × 3                                                                 times                5   [(Et)(Me).sub.2 C.CH.sub.2 ].sub.2 Si(OMe).sub.2                                            290.7                                                                              0.6900                                                                             20   TIBAL                                                                              200  -5  15  1.1   wash × 3                                                                times dry            Com-                                                                          parison                                                                       1      --         --   --   --   TEAL 100  0   30  3.0   wash × 1                                                                time                 2   (Me).sub.2 Si(OMe).sub.2                                                                    120.1                                                                              0.6802                                                                              7   TEAL  80  5   30  2.1   dil × 3                                                                 times                Refer-                                                                        ence                                                                          1   (C.sub.6 H.sub.5).sub.2 Si(OMe).sub.2                                                       --   --   15   TEAL 150  0   30  2.9   wash × 1                                                                time                 __________________________________________________________________________     Note:                                                                         .sup.1) TIBAL: triisobutylaluminum                                            .sup.2) dil: dilution; wash: washing; dry: drying                             .sup.3) diluted with nheptane                                            

APPLICATION EXAMPLE 1 Polymerization of Propylene

2 ml of a solution containing 0.1 mole of triethylaluminum in 1000 ml ofn-heptane, and 2 ml of a solution containing 0.01 mole ofdi-n-hexyldimethoxysilane in 1000 ml of n-heptane were mixed, held for 5minutes and charged in a stainless autoclave of 1500 ml, equipped with astirrer, under nitrogen atmosphere. Then, 600 ml of hydrogen gas as amolecular weight regulator and 1000 ml of liquid propylene were added tothe reaction system under pressure and the temperature of the reactionsystem was raised to 70° C. 40 mg of the catalyst component obtained inExample 1 was introduced into the reaction system and polymerization ofpropylene was carried out for 1 hour. After the polymerization, theunreacted propylene was purged, thus obtaining a white polypropylenepowder having an HI of 98.4%. The quantity of polypropylene formed(C_(E)) was 47.6 kg per Component A 1 g·1 hour.

The catalyst component obtained in Example 1 was charged in a glassvessel rinsed with nitrogen gas, sealed and stored at 15° C. for 4 days,10 days and 20 days and then subjected to polymerization of propylene.The polymerization of propylene was carried out in the same manner asdescribed above to obtain results shown in Table 2, from which it isapparent that deterioration after storage is little. In thesepolymerizations, there was found no fine powder with a grain size of atmost 150 μm.

APPLICATION EXAMPLES 2 TO 7

The polymerization of propylene was carried out in an analogous mannerto Application Example 1, except using the catalyst components obtainedin Examples 2 to 5 instead of the catalyst component obtained in Example1 and using the electron-donating compounds shown in Table 2 instead ofthe di-n-hexyldimethoxysilane or not using them, thus obtaining resultsshown in Table 2.

APPLICATION EXAMPLES 8 TO 13

The polymerization of propylene was carried out in an analogous mannerto Application Example 1, except using the catalyst components obtainedin Comparative Examples 1 to 3 and Reference Example 1 instead of thecatalyst component obtained in Example 1 and using the electron-donatingcompounds shown in Table 3 instead of the di-n-hexyldimethoxysilane andnot using them.

                  TABLE 2                                                         ______________________________________                                        Appli-                                                                              Cata-                       C.sub.E                                     cation                                                                              lyst     Electron- Storage  (Kg/g ·                            Ex-   Com-     Donating  Temp. Days Component                                                                             HI                                ample ponent   Compound  (°C.)                                                                        (day)                                                                              A · hour)                                                                    (%)                               ______________________________________                                        1     Example  (1)       --*   --*  47.6    98.4                                    1                  15     4   48.5    98.1                                                       "     10   46.0    98.3                                                       "     20   44.5    98.1                              2     Example  (2)       --    --   48.3    98.3                                    2                  5      4   47.1    97.9                                                       "     10   44.9    98.1                                                       "     20   43.3    98.0                              3     Example  (3)       --    --   48.4    98.4                                    3                  0      4   47.4    98.0                                                       "     10   43.6    98.0                                                       "     20   45.2    98.2                              4     Example  (4)       --    --   46.5    98.1                                    4                  0      4   45.9    98.3                                                       "     10   43.1    97.9                                                       "     20   42.7    98.2                              5     Example  (5)       --    --   49.5    98.3                                    5                  0      4   47.0    98.0                                                       "     10   45.8    98.2                                                       "     20   45.7    98.2                              6     Example  (6)       --    --   21.8    94.5                                    5                                                                       7     Example  --        --    --   47.9    93.2                                    4                                                                       ______________________________________                                    

                  TABLE 3                                                         ______________________________________                                        Appli-                                                                              Cata-                       C.sub.E                                     cation                                                                              lyst     Electron- Storage  (Kg/g ·                            Ex-   Com-     Donating  Temp. Days Component                                                                             HI                                ample ponent   Compound  (°C.)                                                                        (day)                                                                              A · hour)                                                                    (%)                               ______________________________________                                         8    Com-     (3)       --    --   47.5    92.1                                    parison            0     20   45.8    92.6                                    Example                                                                       1                                                                        9    Com-     --        --    --   32.4    65.1                                    parison                                                                       Example                                                                       1                                                                       10    Com-     (7)       --    --   20.4    94.2                                    parison            5     10   19.1    94.0                                    Example                                                                       2                                                                       11    Com-     (6)       --    --   16.8    86.3                                    parison                                                                       Example                                                                       2                                                                       12    Com-     (1)       --    --    26.8** 91.8                                    parison                                                                       Example                                                                       3                                                                       13    Refer-   (8)       --    --   33.4    97.2                                    ence                                                                          Example                                                                 ______________________________________                                         Note in Tables 2 and 3                                                        *"--" means an experiment immediately after preparation of Catalyst           Component.                                                                    **2.0% by weight of polymer fine powder of 150 μm or less was formed.      Electrondonating compound (1): (nHe).sub.2                                    Electrondonating compound (2): [(nPr)(Me)CH].sub.2                            Electrondonating compound (3): [(Et)(Me).sub.2 C].sub.2                       Electrondonating compound (4): [(Me).sub.3 C.CH.sub.2 ].sub.2                 Electrondonating compound (5): [(Et)(Me).sub.2 C.CH.sub.2 ].sub.2             Si(OMe).sub.2                                                                 Electrondonating compound (6): (Me).sub.2                                     Electrondonating compound (7): [(Pr)(Me)CH].sub.2                             Electrondonating compound (8): [(C.sub.6 H.sub.5).sub.2 Si(OMe).sub.2    

EXAMPLE 6 Preparation of Catalyst Component A

A flask of 200 ml, equipped with a dropping funnel and stirrer, wasreplaced with nitrogen, in which 5 g of silicon oxide (commercial name:G-952, manufactured by DAVISON Co.), calcined in a nitrogen stream at200° C. for 2 hours and 700° C. for 5 hours, and 40 ml of n-heptane werethen charged. Further, 20 ml of a 20% heptane solution (commercial name:MAGALA BEM, manufactured by Texas Alkyls Co.) of n-butylethylmagnesium(hereinafter referred to as BEM) was added thereto and stirred at 90° C.for 1 hour.

The thus obtained suspension was cooled at 0° C, to which a solution of11.2 g of tetraethoxysilane dissolved in 20 ml of n-heptane was dropwiseadded for 30 minutes from the dropping funnel. After the dropwiseaddition, the suspension was heated to 50° C. for 2 hours and stirred at50° C. for 1 hour. After the reaction, the supernatant was removed bydecantation and the resulting solid product was washed with 60 ml ofn-heptane at room temperature, followed by removing the supernatant bydecantation. This washing treatment with n-heptane was further repeated4 times.

50 ml of n-heptane was added to the solid to form a suspension, to whicha solution of 8.0 g of 2,2,2-trichloroethanol dissolved in 10 ml ofn-heptane was dropwise added at 25° C. for 15 minutes from the droppingfunnel. After the dropwise addition, the mixture was stirred at 25° C.for 30 minutes. After the reaction, the mixture was washed at roomtemperature with 60 ml of n-heptane 2 times and with 60 ml of toluene 3times. Analysis of the resulting solid told that it contained 36.6% ofSiO₂, 5.1% of magnesium and 38.5% of chlorine.

To Solid Component I obtained as described above were added 10 ml ofn-heptane and 40 ml of titanium tetrachloride, followed by raising thetemperature to 90° C., to which a solution of 0.6 g of di-n-butylphthalate dissolved in 5 ml of n-heptane was added for 5 minutes.Thereafter, the mixture was heated to 115° C. and reacted for 2 hours.The temperature being lowered to 90° C., the supernatant was removed bydecantation, followed by washing with 70 ml of n-heptane 2 times.Furthermore, 15 ml of n-heptane and 40 ml of titanium tetrachloride wereadded to the mixture and reacted at 115° C. for 2 hours. After thereaction, the resulting solid material was washed with 60 ml of n-hexaneat room temperature 8 times and then subjected to drying under reducedpressure at room temperature for 1 hour to obtain 8.3 g of a catalyticcomponent (Component A) containing, in addition to 3.1% of titanium,silicon oxide, magnesium, chlorine and di-n-butyl phthalate.

Previous Polymerization

1.9 g of Component A, obtained as above, and 280 ml of n-heptane werecharged in a reactor of 500 ml equipped with a stirrer in a nitrogenatmosphere and cooled to 5° C. with agitation. A solution oftriethylaluminum (TEAL) in n-heptane (2.0 mols/l) and a solution ofdi-n-hexyldimethoxysilane in n-heptane (1.0 mol/l) were added thereto insuch a manner that the concentrations of TEAL anddi-n-hexyldimethoxysilane be respectively 80 millimols/l and 8millimols/l in the reaction system, followed by stirring for 5 minutes.Then, after the system was evacuated, propylene gas was fed thereto andpolymerized for 30 minutes. After the polymerization, the propylene gasof gaseous phase was purged with nitrogen gas and n-heptane at 5° C. wasadded to the system to dilute by 5 times, thus preparing a slurry of thecatalytic component. When a part of the slurry was taken and dried, andthe quantity of magnesium contained in the catalyst component wasmeasured, the quantity of the previous polymerization was 3.0 g per 1 gof Component A.

Furthermore, the volume of the di-n-hexyldimethoxysilane and theelectron density of oxygen atoms in methoxy groups were calculated asdescribed above to obtain results shown in Table 4.

EXAMPLES 7 TO 11

A catalyst component was prepared by carrying out the previouspolymerization of Component A in an analogous manner to Example 6,except using a silane compound shown in Table 4 instead of thedi-n-hexyldimethoxysilane, a trialkylaluminum shown in Table 4 with aconcentration shown in Table 4 instead of TEAL and previouspolymerization conditions shown in Table 4, in the previouspolymerization of Example 4.

In Table 4 are shown calculated values as to the volume and the electrondensity of oxygen atoms in the methoxy groups of each of the silanecompounds.

COMPARATIVE EXAMPLE 4

A catalyst component was prepared by carrying out the previouspolymerization of Component A in an analogous manner to Example 6,except not using the di-n-hexyldimethoxysilane under the previouspolymerization conditions shown in Table 4, in the previouspolymerization of Example 6.

COMPARATIVE EXAMPLE 5

A catalyst component was prepared by carrying out the previouspolymerization of Component A in an analogous manner to Example 6,except using dimethyldimethoxysilane instead of thedi-n-hexyldimethoxysilane and previous polymerization conditions shownin Table 4 in the previous polymerization of Example 6.

COMPARATIVE EXAMPLE 6

A catalyst component (Component A) was prepared by repeating theprocedure of Example 6, except not carrying out the previouspolymerization.

EXAMPLE 12 Preparation of Catalyst Component A

After silicon oxide and BEM were contacted in an analogous manner toExample 6 except that the stirring time at 90° C. was 2 hours, thesupernatant was removed by decantation, the resulting solid product waswashed at room temperature with 50 ml of n-heptane and further subjectedto removal of the supernatant liquid by decantation. This washingtreatment with the n-heptane was carried out 4 times.

20 ml of n-heptane was added to the above described solid to prepare asuspension, to which a solution of 9.6 g of 2,2,2-trichloroethanoldissolved in 10 ml of n-heptane was dropwise added at 0° C. for 30minutes from the dropping funnel. After stirring at 0° C. for 1 hour,the mixture was heated at 80° C. over 1 hour and the stirring wascontinued at 80° C. for 1 hour. After the reaction, the mixture waswashed with 50 ml of n-heptane 2 times and with 50 ml of toluene 3 timesat room temperature to obtain a solid (Solid Component I).

20 ml of toluene and 0.6 g of di-n-butyl phthalate were added to thethus obtained Solid Component I and reacted at 50° C. for 2 hours. Then,30 ml of titanium terachloride was added thereto and reacted at 50° C.for 2 hours. The resulting solid material was then washed with 50 ml ofn-hexane at room temperature 8 times and dried under reduced pressure atroom temperature to obtain 7.7 g of Component A containing, in additionto 3.0% of titanium, silicon oxide, magnesium, chlorine, di-n-butylphthalate.

Previous Polymerization

A catalytic component was prepared by carrying out the previouspolymerization in an analogous manner to Example 6 except usingComponent A obtained as described above and previous polymerizationconditions as shown in Table 4.

COMPARATIVE EXAMPLE 7

A catalytic component was prepared in an analogous manner to Example 12except not using bis(2,2-dimethylpropyl)dimethoxysilane under previouspolymerization conditions shown in Table 4.

REFERENCE EXAMPLE 2

A catalytic component was prepared in an analogous manner to Example 12except using diphenyldimethoxysilane instead of thebis(2,2-dimethylpropyl)dimethoxysilane in the previous polymerization ofExample 12 under previous polymerization conditions shown in Table 4.

                                      TABLE 4                                     __________________________________________________________________________                                               Previous Polymerization            Silane Compound                  AlR.sub.3 Tem-    Amount of                                         Electron                                                                           Concen-   Concen-                                                                            per-    Polymer-                   Ex-               Volume                                                                             Density                                                                            tration   tration                                                                            ature                                                                             Time                                                                              ization                                                                             After-               ample                                                                             Formula       (Å.sup.3)                                                                      (A.U.)                                                                             (mmol/l)                                                                           Name (mmol/l)                                                                           (°C.)                                                                      (min)                                                                             (g/g) treatment.sup.2)     __________________________________________________________________________    Ex-                                                                           ample                                                                         6   (n-He).sub.2 Si(OMe).sub.2                                                                  290.4                                                                              0.6941                                                                              8   TEAL  80  5   30  3.0   dil × by                                                                5                                                                             times                7   [(Et)(Me).sub.2 C].sub.2 Si(OMe).sub.2                                                      256.4                                                                              0.7223                                                                             10   TEAL 100  0   60  4.3   wash × 1                                                                time                 8   (n-Bu).sub.2 Si(OMe).sub.2                                                                  222.1                                                                              0.6892                                                                             10   TEAL 100  -5  60  3.3   wash.sup.3)                                                                   × 1                                                                     time,                                                                         dry.sup.4)           9   (t-Bu).sub.2 Si(OMe).sub.2                                                                  222.4                                                                              0.7300                                                                             10   TIBAL.sup.1)                                                                       100  0   120 7.9   dil × by                                                                3                                                                             times                10  [(n-Pr)(Me)CH].sub.2 Si(OMe).sub.2                                                          256.5                                                                              0.6980                                                                             20   TIBAL                                                                              200  -5  30  1.7   wash × 3                                                                times, dry           11  [(Et)(Me).sub.2 C.CH.sub.2 ].sub.2 Si(OMe).sub.2                                            290.7                                                                              0.6900                                                                             10   TEAL 100  -5  60  3.3   wash × 3                                                                times                12  [(Me).sub.3 C.CH.sub.2 ].sub.2 Si(OMe).sub.2                                                256.2                                                                              0.6934                                                                             10   TEAL 100  0   120 1.6   wash × 3                                                                times, dry           Com-                                                                          parison                                                                       4      --         --   --   --   TEAL 100  0   60  4.2   wash × 1                                                                time                 5   (Me).sub.2 Si(OMe).sub.2                                                                    120.1                                                                              0.6802                                                                              8   TEAL 100  5   30  1.4   dil × by                                                                3 times              6      --         --   --   --   TEAL 100  0   120 1.5   wash × 3                                                                times, dry           Refer-                                                                        ence                                                                          2   (C.sub.6 H.sub.5).sub.2 Si(OMe).sub.2                                                       --   --   10   TEAL 100  0   120 1.7   wash × 1                                                                time                 __________________________________________________________________________     Note:                                                                         .sup.1) TIBAL: triisobutylaluminum                                            .sup.2) dil: dilution; wash: washing; dry: drying                             .sup.3) washed with 100 ml of hexane                                          .sup.4) dried under reduced pressure at room temperature for 1 hr        

APPLICATION EXAMPLE 14 Polymerization of Propylene

4 ml of a solution containing 0.1 mole of triethylaluminum in 1000 ml ofn-heptane, and 2 ml of a solution containing 0.01 mole ofdi-t-amyldimethoxysilane in 1000 ml of n-heptane were mixed, held for 5minutes and charged in a stainless autoclave of 1500 ml, equipped with astirrer, under nitrogen atmosphere. Then, 1000 ml of hydrogen gas as amolecular weight regulator and 1000 ml of liquid propylene were added tothe reaction system under pressure and the temperature of the reactionsystem was raised to 70° C. 40 mg of the catalyst component obtained inExample 6 was introduced into the reaction system and polymerization ofpropylene was carried out for 1 hours. After the polymerization, theunreacted propylene was purged, thus obtaining a white polypropylenepowder having an III of 97.4%. The quantity of polypropylene formed(C_(E)) was 23.4 kg per Component A 1 g. 1 hour.

The catalyst component obtained in Example 6 was charged in a glassvessel replaced with nitrogen gas, sealed and stored at 5° C. for 4 days10 days and 20 days and then subjected to polymerization of propylene.The polymerization of propylene was carried out in the same manner ascribed above to obtain results shown in Table 5, from which it isapparent that deterioration after storage is little. In thesepolymerizations, there was found no fine powder with a grain size of atmost 150 μm.

APPLICATION EXAMPLES 15 TO 20

The polymerization of propylene was carried out in an analogous mannerto Application Example 14, except using the catalyst components obtainedin Examples 7 to 11 instead of the catalyst component obtained inExample 6 and using the electron-donating compounds shown in Table 5 inApplication Examples 17 and 20 in-stead of the di-t-amyldimethoxysilaneor not using them, thus obtaining results shown in Table 5.

APPLICATION EXAMPLES 21 TO 24

The polymerization of propylene was carried out in an analogous mannerto Application Example 14, except using the catalyst components obtainedin Comparative Examples 4 to 6 instead of the catalyst componentobtained in Example 6 and using the electron-donating compounds shown inTable 6 instead of the di-t-amyldimethoxysilane in Application Example23, thus obtaining results shown in Table 6.

APPLICATION EXAMPLES 25 TO 27

The polymerization of propylene was carried out in an analogous mannerto Application Example 14, except using the catalytic componentsobtained in Example 12, Comparative Example 7 and Reference Example 2instead of the catalytic component obtained in Example 6, usingtriisobutylaluminum instead of TEAL, adjusting the polymerizationtemperature to 80° C. and using the electron-donating compounds shown inTable 6 instead of the di-t-amyldimethoxysilane or not using theelectron-donating compounds, thus obtaining results shown in Table 6.

                  TABLE 5                                                         ______________________________________                                        Appli-                                                                              Cata-                       C.sub.E                                     cation                                                                              lyst     Electron- Storage  (Kg/g ·                            Ex-   Com-     Donating  Temp. Days Component                                                                             HI                                ample ponent   Compound  (°C.)                                                                        (day)                                                                              A · hour)                                                                    (%)                               ______________________________________                                        14    Example  (3)       --*   --*  23.4    97.4                                    6                  5      4   23.5    97.7                                                       "     10   22.6    97.6                                                       "     20   21.8    97.7                              15    Example  (3)       --    --   23.2    97.6                                    7                  0      4   23.6    97.3                                                       "     10   22.3    98.0                                                       "     20   22.7    97.6                              16    Example  (3)       --    --   23.7    98.1                                    8                  23     4   21.8    97.9                                                       "     10   22.3    97.8                                                       "     20   22.3    98.2                              17    Example  (9)       --    --   22.4    97.5                                    9                  0      4   21.9    97.6                                                       "     10   21.6    97.1                                                       "     20   20.8    97.8                              18    Example  (3)       --    --   24.8    97.9                                    10                 0      4   25.1    97.8                                                       "     10   24.2    97.6                                                       "     20   24.5    97.8                              19    Example  (3)       --    --   23.7    98.1                                    11                                                                      20    Example  (6)       --    --   13.1    94.2                                    7                                                                       ______________________________________                                    

                  TABLE 6                                                         ______________________________________                                        Appli-            Electron- C.sub.E                                           cation Catalyst   Donating  (Kg/g · Component                                                                HI                                    Example                                                                              Component  Compound  A · hour)                                                                        (%)                                   ______________________________________                                        21     Comparison (3)       23.3        91.7                                         Example 4                                                              22     Comparison (3)       13.1        93.0                                         Example 5                                                              23     Comparison (6)       9.5         87.1                                         Example 5                                                              24     Comparison (3)       9.7**       93.7                                         Example 6                                                              25     Example 12 --        12.1        92.8                                  26     Comparison --        12.8        73.0                                         Example 7                                                              27     Reference  (8)       10.4        92.3                                         Example 2                                                              ______________________________________                                         Note in Tables 5 and 6                                                        *"--" means an experiment immediately after preparation of Catalyst           Component.                                                                    **1.8% by weight of polymer fine powder of 150 μm or less was formed.      Electrondonating compound (3): [(Et)(Me).sub.2 C].sub.2 Si(OMe).sub.2         Electrondonating compound (6): (Me).sub.2 Si(OMe).sub.2                       Electrondonating compound (8): (C.sub.6 H.sub.5).sub.2 Si(OMe).sub.2          Electrondonating compound (9): (tBu).sub.2 Si(OMe).sub.2                 

UTILITY AND POSSIBILITY

According to the present invention, there can be obtained advantagesthat the strength of the catalytic component can be increased by theabove described features and the catalytic component is capable ofmaintaining a high activity and exhibiting a high stereoregularity inthe (co)polymerization of α-olefins, and in particular, the washedcatalytic component is capable of preventing from deterioration duringstorage.

We claim:
 1. In an olefin catalyst component prepared by bringing asolid comprising (a) titanium, (b) magnesium, and (c) anelectron-donating compound into contact with (d) an olefin in thepresence of (e) an organoaluminum co-catalyst and (f) a silane compoundwherein the improvement comprises:i) the silane compound being adimethoxy group containing a molecular structure represented by thegeneral formula R¹ R² Si(OCH₃)₂ where R¹ and R² are, same or different,aliphatic hydrocarbon groups with 1 to 10 carbon atoms and having amolecular volume of 200 to 500 Å³ and an electron density of oxygenatoms in the methoxy group, calculated similarly, ranging from 0.685 to0.800 A.U. (atomic units).
 2. The catalyst component of claim 1 whereinthe silane compound has a molecular volume of from about 230 to 500 Å³.3. In an olefin catalyst component prepared by bringing a solidcomprising (a) titanium, (b) magnesium, and (c) an electron-donatingcompound into contact with (d) an olefin in the presence of (e) anorganoaluminum co-catalyst and (f) a silane compound wherein theimprovement comprises:i) the silane compound being a dimethoxy groupcontaining a molecular structure represented by the general formula R¹R² Si(OCH₃)₂ where R¹ and R² are, same or different, aliphatichydrocarbon groups with 1 to 10 carbon atoms and having a molecularvolume of 170° to 500 Å³ and an electron density of oxygen atoms in themethoxy group, calculated similarly, ranging from 0.690 to 0.800 A.U.(atomic units).